The present invention relates to a new and distinct cultivar of Coreopsis plant, botanically of hybrid origin and known as Coreopsis ‘Star Cluster’ and will be referred to hereinafter by its cultivar name, ‘Star Cluster’. The new cultivar of Coreopsis is an herbaceous perennial grown for landscape and container use.
The new invention arose from an ongoing controlled breeding program in Hubbardston, Mass. The objective of the breeding program is to develop hybrid cultivars of Coreopsis with unique and superior garden attributes. In particular, to develop cultivars that are long-lived, sturdy, exhibit a true perennial habit and cold hardy to at least U.S.D.A Zone 5 in a wide range of flower colors and plant forms. The inventor collected seed in the wild from five different species that are not commercialized and made six generations of crosses to produced interspecific hybrids to utilize in his breeding work.
The Inventor made a controlled cross in summer of 2007 in his test garden in Hubbardston, Mass. between Coreopsis ‘Redshift’ (U.S. Plant Pat. No. 20,412) as the female parent and an unnamed F1 Coreopsis rosea×complex hybrid as the male parent. ‘Star Cluster’ was selected in September 2008 as a single unique plant amongst the resulting seedlings.
Asexual reproduction of the new cultivar was first accomplished by stem cuttings under the direction of the Inventor in Kensington, Conn. in September of 2008. The characteristics of this cultivar have been determined to be stable and are reproduced true to type in successive generations.